There has been known such a conventional problem that, when vehicles pass through a track branch, frozen snow drops down due to vibrations of the vehicles, or dropping frozen snow hits ballast, so that the ballast jumps up as scattered stones or the like; and thus the dropping frozen snow or the scattered stones may be caught between a stock rail and a tongue rail, which hinders switching of the tongue rail. Hence, various developments and studies have been conducted on foreign matter removing apparatuses for use at a track branch.
For example, Japanese Patent Laid-Open No. H07-054317 discloses a foreign matter removing apparatus at a track branch that removes foreign matters between a stock rail and a tongue rail so as to prevent switching of the track branch from being disable due to dropping frozen snow or scattered stones.
The foreign matter removing apparatus at a track branch described in Japanese Patent Laid-Open No. H07-054317 is a foreign matter removing apparatus at a track branch that removes foreign matters having dropped between the stock rail and the tongue rail at the track branch, wherein each piping unit is installed to a side surface of the stock rail opposing the tongue rail in accordance with a length of the branch track, air injection nozzle units each having multiple injection ports are disposed at multiple positions with intervals in the longitudinal direction of this piping unit such that the injection orientation of each nozzle unit is slightly directed to the tongue rail, a pressured air source device is provided in the vicinity of the track branch, and the pressured air source device is connected to each pressured air supply passage through an opening/closing switching mechanism thereof so as to supply the pressured air to each piping unit.
Japanese Patent Laid-Open No. 2010-007423 discloses a foreign matter removing apparatus at a track branch capable of removing foreign matters between rails at a crossing section of the track branch.
The foreign matter removing apparatus at a track branch described in Japanese Patent Laid-Open No. 2010-007423 is installed at a track branch including stock rails, and tongue rails that can come into contact with or apart from the stock rails, and removes foreign matters having dropped between the rails by injecting compressed air, wherein this foreign matter removing apparatus is disposed at a crossing section where rails intersect each other, which is located at a backward position opposite to a frontward position of the track branch where the stock rail and the tongue rail are able to come into contact with each other, and the foreign matter removing apparatus includes a nozzle unit for injecting compressed air, and an air supply device for supplying the compressed air to the nozzle unit, wherein the nozzle unit is disposed in the frontward position in the crossing section, and includes injection ports having apertures for injecting the compressed air backward in the crossing section.
Both the foreign matter removing apparatuses of Japanese Patent Laid-Open No. H07-054317 and Japanese Patent Laid-Open No. 2010-007423 at the track branches are very useful for removing dropping frozen snow and scattered stones.